Warm v2v migration- vmware vm guest migration without powering down.

Introduction

I recently had to migrate a production webserver from esxi 3.5 free host to an esxi 4.1 host.
I wanted to minimize production downtime. I couldn't use veeam backup because the source host was not licensed.

old = esxi 3.5 free
new = esxi vsphere 4.1 (setup up new host networks the same as old host)

using latest veeam fastscp:

old host copy:

1.remove all snapshots from vm

2.from old host to new host copy...

vm.vmdk

vm.vmsd

vm.vmx

vm.vmxf

3. take a snapshot of old vm (arrange that noone make updates to website during this time. all this data will be lost.)

A small change would reduce 30 seconds of downtime to less than a second:

Instead of shutting down the old machine, just pull the patch cable out of the old NIC and put it into the new NIC. You could do this virtually (slower) or physically if the machines are in the same room. If physically, just make sure the virtual switch is connected to the NIC in the new machine.

The American scientist Paul Ehrlich once said, "To err is human, but to really foul things up you need a computer." At risk of hyperbole, it is my humble opinion that a greater truth has never been uttered.